Intrinsically Low Thermal Conductivity in BiSbSe3: A Promising Thermoelectric Material with Multiple Conduction Bands

• DOI: 10.1002/adfm.201806558
• Publication Date: 2018-11-27T07:39:51Z
• Authors: Xiaoying Liu; Dongyang Wang; Haijun Wu; Jinfeng Wang; Yang Zhang; Guangtao Wang; Stephen J. Pennycook; Li‐Dong Zhao
• Keywords: Orthorhombic crystal system; Figure of Merit

Abstract Bi 2 Se 3 , as a Te‐free alternative of room‐temperature state‐of‐the‐art thermoelectric (TE) Te has attracted little attention due to its poor electrical transport properties and high thermal conductivity. Interestingly, BiSbSe product alloying 50% Sb on sites, shows outstanding electron phonon transports. possesses orthorhombic structure exhibits multiple conduction bands, which can be activated when the carrier density is increased ≈3.7 × 10 20 cm −3 through heavily Br doping, resulting in simultaneously enhancing conductivities Seebeck coefficients. Meanwhile, an extremely low conductivity (≈0.6–0.4 W m −1 K at 300–800 K) found . Both first‐principles calculations elastic measurements show strong anharmonicity support ultra‐low Finally, maximum dimensionless figure merit ZT ∼ 1.4 800 achieved BiSb(Se 0.94 0.06 ) comparable most n ‐type TE materials. The present results indicate that new robust candidate for power generation medium‐temperature range.